Generally, when foreign matter enters a deep position in a body, a capsule of connective tissue mainly consisting of fibroblasts and collagen is formed so as to cover the foreign matter, and isolates the foreign matter in the body. A method is disclosed using this self-protective reaction to form tubular tissue derived from a living body with living cells in a living body (see Patent Literatures 1 to 4 and Non-patent Literature 1).
These literatures disclose methods for forming tissue derived from a living body having a relatively simple structure, and further, production is desired of tissue derived from a living body having a complicated structure with an ampulla and a leaflet, such as an aortic sinus (Valsalva sinus) of an aorta. The aortic sinus (Valsalva sinus) includes an ampulla with a blood vessel wall expanding radially outward, and a plurality of leaflets that open/close a blood vessel inside and on an upstream side of the ampulla, and the ampulla functions as an escape path for blood when a valve opens, and functions as a reservoir for the blood when the valve closes.
As means for producing a valved artificial blood vessel including such an ampulla and a leaflet, Patent Literature 5 discloses an artificial heart valve containing biocompatible block copolymer and a scaffold for a blood vessel structure.
In the technique disclosed in Patent Literature 5, first, fibers are deposited on a valve model including a plurality of model parts by electospinning to construct a mesh structure. Then, the model parts are released from the mesh structure to complete a scaffold of the valve model. The scaffold has a mesh-like structure formed by polymer fibers. Cells (endothelial cells or myofibroblasts) are cultured on the scaffold, and thus the cells grow in the mesh structure to form a valved artificial blood vessel.